Cameron, did you have a specific edition of D&D in mind or are you interested in RPGs in general? Are there particular genres you prefer such as fantasy, sci-fi, steampunk, etc.? There are tons of different game systems out there, and even D&D has different versions. If you narrow down what you're looking for, it could help you find people to assist you. There's also a number of GMs here on roll20 that sometimes run one shots for various game systems to introduce new players. You might consider browsing the Looking For Group listings and the Looking For Group forums for those kinds of games. Even if you just see one that sounds interesting to you, there's no harm in asking the GM if they're willing to teach a new player. The Looking For Group listings even includes a checkbox to help you narrow down to campaigns that welcome new players.